Improvement in lifting-jacks



s. E. MosHEP..

LIFTING-J'ACKS.

m1911161 Aug. 28,1877.

lWITNESSES ATTORNEY i UNITED STATES PATENT OFFICE.

SAMUEL E. MOSHER, OF OHILLIOOTHE, OHIO.`

IMPROVEMENT IN ALIFTING-JACKS.

Specification forming part of Letters Patent No. 194,711, dated August 28, 1877; application filed May 12, 1877.

To all whom 'it may concern:

Be it known that I, SAMUEL EARL MosHEE, of Chillicothe, in the county of Ross and State of Ohio, have invented a new and valuable Improvement in Lifting-Jacks; and l do hereby declare that the following is a full, clear, and exact description of the construction and operation of the same, reference being had to the annexed drawings, making a part of this specification, and to the letters and figures`` of reference marked thereon.

Figure 1 of the drawings is a representation of a perspective view of my improved liftingjack, and Fig. 2 is a vertical sectional view thereof.

This invention has relation to improvements 'inlifting-jacks that are principally constructed of cast-iron, and are adjustable at any height to support the object to be lifted; and it consists in the arrangement and novel construction of its parts, and in their combination, as will be hereinafter more fully described and claimed. i

In the annexed drawings, A designates the hollow standard or frame, cast in one piece, or made in two symmetrical sections, adapted to be bolted together, in any suitable manner. rThis standard is provided with guide-striped upon its opposite inner walls, between which and the rear wallof the standard is arranged a lifting-bar, B, having a heel, b, Working in a slot, b', in said rear wall, that prevents the lifting-barfrom undue upward extension.

Bar B'is provided on one of its edges with a series of teeth, c, downwardly inclined, with which the teeth o' of a lifting-block, C, are adapted to engage. This block C has sufficient outward play in the standard to clear the teeth of the lifting-bar, but is limited in its vertical movements by a shelf or ledge, e, above and a shoulder, e', below, Athe latter being in the upper ends of one or both of the guide-strips aforesaid.

The side walls of the standard are provided i near their upper ends with trunnions D, upon which are secured, in any suitable manner, hangers E. These hangers afford bearings in their lower ends for trunnions D of a vertically-vibrating lever, E', that is notched between said trunnions to admit the lifting-block aforesaid, and is pivoted by means of a bolt, f, to the same.

When this lever is drawn outward the lifting-block will be disengaged from the liftingbar, and its end maythen be vibrated upward. If now the said lever be thrown down it will raise the said block and actuate the lifting-bar, which will be extended from the standard.

l Lever E is longitudinally slotted, as shown at g, and in this slot is received a toothed circular segmentF, the ends of which are-secured to the standard above and below the liftingblock. In the slot g, outsidel of the segment, is journaled, in curvedslots i in the arms of said lever, a toothed segment-lever, G, that engages the segment F aforesaid. This lever G forms, with the toothed segment F and lever E', a compound lever of great power, and, as it is journaled in slotsz' in the said lever E', it may readily be disengaged from the segment aforesaid and take fresh hold.

In order to take the strain off the operating mechanism the standard is provided with spaced perforations h on the same level at each side, through which a strong wedge-shaped bar, H, is passed directly under the lifting-block, and preventing the same from slipping backward; and in order to hold the said lever E from upward vibration when the lifting-bar is under strain I employa pawl, K, that straddles or lies over the periphery of the segment, and is pivoted to the lever E aforesaid.

Above the ledge e, against which the liftingblock abuts, is arranged a box, I, having vertical play, and containing a spring-actuated pawl, I', composed of a body having several teeth engaging with those of the lifting-bar, and an operating-handle, j, that extends through a perforation in the box and standard beyond the latter.

By drawing on this handle the pawl will recede in its box from the lifting-bar and clear the teeth thereof, and the said bar may then be lowered by disengaging the lifting-block aforesaid from it. In the upward movements of the lifting-bar the pawl readily recedes, owing to the yielding of the spring s, but themoment` this movement ceases it takes hold and operates as an ordinary pawl. Should it not take hold when the object has attained the desired height,

and causing it to engage the teeth of the lifting-bar. In being thus raised, a spur, m, working in a recess, n, ofthe standard compresses a spring, o, seated therein, which, upon the removal of the Wedge,willreact and force thebox back upon its ledge.

The lifting-bar above described maybe sometimes made hollow, and in this hollow a supplemental'bar may be placed, which, being drawn out and supported in this extended state by a pin, bolt,'or-other'equivalent device, will increase the length of the lifting-bar and dispense with the usual blocking in raising high objects.

Having described my invention, vwhat I claim as new, and desire to secure by Letters Patent, is-

1. 'Thecombinatiom with: the lifting-bar B and hollow/standard A, vhaving shelf e, of' the spring factuated v.pawl I `and its inclosing movablebox I, substantially as specified.

2. :The standard A, having registering-perforations hl below theJ lifting-block and below thelocking-pawl, adapted to receive a keywedge, substantially as specified.

. 2 wenn 3. The combination, with the lifting-bar B and lifting-block U, of the hollow standard A, having trunnions D, the vertically-vibrating hangers E.' the lever E', having trunnions D journaled in said hangers, the pivot-pin f, toothed segment F, and toothed segment-lever G, substantially as specied.

4. The combination, with the segment F and the standard and raising mechanism of a lifting-jack, ofthe lever E', having longitudinal slot g and curved slots t', and the segmentlever G journaled in said slots and engaging said segment, substantially as specified.

5.v The combination, with the verticallymovable pawl-box and pawl, of a hollow standard recessed to receive said pawl-box, and provided with perforations at the heel of said box, substantially as-specied.

In testimony that-I claim the above I have hereunto subscribed vmy name in the presence of two witnesses.

SAMUEL EARL MOSHER Witnesses:

GEORGE EARL MosHER, E. K. ULEGK. 

